WorldWide Drilling Resource

32 JANUARY 2021 WorldWide Drilling Resource ® 302-684-3197 FAX: 302-384-0643 142 Broadkill Rd. • Milton, DE 19968 email : Manufacturers of Slotted & Perforated Pipe ranging from ½” to 24” diameter Atlantic Screen & Mfg., Inc. • Well Rehab. Products • Manholes • Bentonite • Filter Sock • Inline Chemical Mixers • Sampling Bailers • Clear PVC Pipe • Locking Caps Robbins Single Shield Bores through Turkey’s Hardest Rock Adapted from Information by Robbins Company Turkey celebrated a milestone in the construction of their Bahçe- Nurdaği High-Speed Railway Tunnel this past year. Initial tunnelling was completed using a 26.2-foot-diameter Robbins Single Shield tunnel boring machine (TBM). Excavated through some of the hardest, most abrasive rock ever encountered in the country, the 5.5-mile-long tunnel was not easy to bore. Tunnelling crews encountered ground conditions ranging from abrasive, interbedded sandstone and mudstone with quartzite veins, to highly weath- ered shale and dolomitic limestone. Deniz Sahin, TBM chief for contractor Intekar Yapi A.Ş., praised the crew, who “acted rapidly and were well organized to overcome the challenging ground conditions with a unique Single Shield TBM for the completion of the first tube.” The TBM’s body, enclosed in a shield slightly smaller than the tunnel diameter, has a cutterhead with a flat, low profile matching the tunnel’s diameter, minimizing face disturbance and preventing large rock collapses. A ring of hydraulic cylinders provided forward thrust with shoes pushing against the tunnel lining. Embedded in the cutterhead, disc cutters were positioned for optimal boring. Utilizing these rolling disc cutters for high thrust created rock fractures, causing chips to break off the face. Another boring factor was the East Anatolian Fault with water in the fault lines and shear zones. After getting stuck in three different fault zones, the TBM’s progress was continued by building bypass tunnels. Several smaller fault zones with exces- sive material flow required ground stabilization and cutterhead cleaning while the dewatering system removed water inflows of almost three gallons per second on average. With the help of a Robbins continuous conveyor system for muck removal, the TBM ultimately achieved up to 1500 feet per month. Sahin commented, “The whole system was quite robust.” Sahin was impressed by the machine’s overall capacity: “The Robbins Single Shield TBM’s motor power, hydraulic power, and cutterhead torque were quite strong. The secondary ventilation and air suction systems inside the TBM were pow- erful. The connections between the gantries, scaffolding systems, walkways, and working areas were good.” Turkey’s tunnel bored by Robbins Single Shield. C&G New Filter for Tailings Applications Adapted from a Press Release by Metso Outotec As part of Metso Outotec’s sustainable technologies, end-to-end solutions, and services for the aggregates, minerals processing, and metals refining industries, the company introduced a new high-capacity filter for demanding tailings applications. Extending their product line, the new Larox ® FFP3716 filter has a compact plate pack design and smart automation to redefine the standard in reliability, capacity, and safety in tailings filtration. Combined with Metso Outotec’s optimized filtration plant design, the FFP3716 filter offers a reliable, cost-efficient, long-term solution for tailings management, even in challenging environments. “Responsible usage of water in the mining industry is the primary driver for increasing interest in tailings dewatering. At Metso Outotec, our goal is to provide holistic tailings management solutions by bringing a step change in the way we view, handle, and manage tailings,” said Geoff Foster, head of tailings filtration a Metso Outotec. “Backed by proven technology and industrial knowledge, our effi- cient dewatering solutions help in maximizing water recovery and reuse. The Larox ® FFP3716 filter represents the most advanced technology currently available for safe and efficient dewatering.” The FFP3716 filter was engineered from top to bottom with optimal safety in mind. It uses the most advanced plate pack design for reduced wear on the plate pack and cloth components, along with ease of operation and spares holding. Also, the new closing and sealing mechanism with individual controlled sealing cylinders ensures squared plate pack at any time, resulting in an extended lifetime for the pack. ENV